1. Field of Invention
This invention relates generally to flow control in downhole completions. Specifically, this invention relates to the control of flow along the length of a horizontal downhole completion.
2. Related Art
Within the oil and gas industry, it is now fairly common to include lateral well bores that extend at an angle from a main vertical well bore. In some cases, the lateral well bores extend in a substantially horizontal direction from the main well bore.
A completion is typically deployed within such lateral well bores. The completion may include sliding sleeves, packers, and sand control equipment. Essentially, hydrocarbons flow from the formation intersected by the lateral well bore, into the lateral well bore, into the completion, and to the surface through the completion and associated tubing string.
However, in lateral well bores, specially those extending in a substantially horizontal direction, the flow rate into the completion is not equal along the length of the completion. Instead, due to the flow friction along the length of the completion, a higher flow rate tends to exist at the near end or xe2x80x9cheelxe2x80x9d of the lateral completion, and a lower flow rate tends to exist at the far end or xe2x80x9ctoexe2x80x9d of the lateral completion. The disparity in flow rate from the xe2x80x9ctoexe2x80x9d to the xe2x80x9cheelxe2x80x9d of the lateral completion, in turn, may lead to premature gas or water coning at the area of higher flow rate and/or may also decrease the total amount of hydrocarbons extracted from the relevant formation.
The prior art would therefore benefit from a system and method for equalizing the flow rate along a lateral completion.
The present invention uses an innovative design for a completion assembly for use in a lateral well bore having a base pipe with a plurality of holes through the sidewall of the base pipe. Flow through the holes is regulated to produce an influx difference between the ends of the base pipe. Flow can be regulated by variably spacing or sizing the holes. Flow can also be regulated by selectively inserting a rod between adjacent splines located on the base pipe to cover and block the flow through certain holes in the base pipe. Flow can also be regulated using a rotatable sleeve circumferentially adjacent to the base pipe such that rotation of the sleeve brings the holes and openings in the pipe and sleeve, respectively, into and out of alignment. A filter can be used to filter sand and other particulates. An erosion inhibitor can be used to extend the useful life of the assembly.